The invention relates to structures which incorporate honeycomb support members for equipment units of systems subjected to shock. It relates more particularly to structures in which it is necessary to reduce the level of shock transmitted from a source to an equipment unit through the structure.
Some hardware systems, such as satellites or their launch vehicles, include relatively fragile equipment units whose operation can be disturbed to a greater or lesser extent by shock transmitted to them through the structure supporting them, especially when the shock is from a source carried by the structure. It is not always possible to have the sources of shock far enough away from the equipment units to be protected, either in small satellites referred to as minisatellites or microsatellites or in large satellites which include a large number of equipment units.
Satellites and launch vehicles often include many mechanisms, in particular pyrotechnic mechanisms, for igniting, moving, deploying, separating or activating the various equipment units and which are the source of intense shock. These include in particular separation mechanisms of launch vehicles and mechanisms for deploying payloads, which tend to be more and more powerful. This leads to a search for solutions which reduce the shock to which systems, and in particular equipment units which are sensitive to shock, are subjected.
It is possible to design relatively complex structures which attenuate shock at connections in the hardware structure supporting a system and which includes a support for an equipment unit which has to be protected because it is sensitive to shock. However, such structures are rarely used because they must be individually designed and appropriate modeling is difficult.
The current trend is to attempt to attenuate shock at source, for example by incorporating an elastomer material to absorb some shock waves. For example, such means halve the power of the shock at frequencies above 1000 Hz in the case of a satellite-borne antenna and solar panel deployment subsystem, for example.
There appears to be no truly effective method of attenuating shock operating on the path of propagation of shock waves and in particular as close as possible to the equipment units to be protected.
The use of honeycomb structure supports to save weight in onboard systems and in particular in satellite-borne systems is known in the art. Such supports are used to mount various equipment units, including those which constitute sources of shock, and in particular pyrotechnic mechanisms of the kind referred to above.
The invention therefore proposes a structure intended to reduce shock transmitted from a source to an equipment unit in a hardware system, which structure incorporates a honeycomb support member carrying the equipment unit to be protected from shock and/or the source.
According to a feature of the invention the structure includes a support member including honeycomb cells which are filled with rigid microgranules.
Accordingly, the microgranules are free to move, slip and rub, and these phenomena attenuate the vibratory waves that propagate in the structure in the event of pyrotechnic shock.
According to a feature of a first embodiment, the structure includes a support member incorporating honeycomb cells filled with microgranules which is mounted between a member carrying a source of shock and a member carrying an equipment unit to be protected from shock.
According to a feature of a second embodiment the structure includes an equipment unit to be protected from shock and/or a source of shock mounted on a support member whose cells are filled with microgranules.
According to a feature of a third embodiment the structure includes a honeycomb cellular support member includes cells filled with microgranules in one or more delimited areas each consisting of a main part where an equipment unit to be protected is mounted and a peripheral extension which borders the main part externally.
According to a feature of a fourth embodiment the structure includes a honeycomb cellular support member includes cells filled with microgranules in one or more delimited areas each consisting of a main part where a source of shock is mounted and a peripheral extension which borders the main part.